He Used To Support This Policy Mother Jones's Nick Baumann notes
that the campaign platform shared by Lieberman and Al Gore during their
2000 presidential run included an expansion of medicare to Americans
aged 55 to 64. That is the exact policy that Lieberman now threatens to
filibuster and vote down. "Lieberman has been moving to the right for
years now," he writes. "The question is, why won't he acknowledge his
shift?"

He Just Hates Liberals The Washington Post's Ezra Klein laments that Lieberman "is forcing liberals to give up yet another compromise. Each time he
does that, he increases the chances of the bill's failure that much
more. And if there's a policy rationale here, it's not apparent to me, or to others who've interviewed him. At this point, Lieberman seems primarily motivated by torturing liberals. That is to say, he seems willing to cause the deaths of hundreds of thousands of people
in order to settle an old electoral score," Klein writes, alluding to
Lieberman's villification by the left following his support for Sen.
John McCain's 2008 presidential campaign. "[T]he underlying dynamic
seems to be that Lieberman will destroy any compromise the left likes."

Dem Leadership Tolerates It Open Left's Chris Bowers wishes they wouldn't.
"Lieberman flip-flipped because he can. No matter what Lieberman does,
the majority of the Democratic Senate caucus won't do anything about
it," he writes. "Nothing Lieberman is doing would be possible without
the ongoing
support of the majority of the Democratic caucus. If Democratic
Senators wanted to punish Lieberman for his consistent transgressions
against the party, they could. [...] Lieberman is simply taking the
power that is being handed to him by the rest of the caucus."

Partisan Opposition Over Saving LivesMatthew Yglesias unleashes,
"The leverage that Lieberman and other 'centrists' have obtained on
this
issue (and on climate change) stems from a demonstrated willingness to
embrace sociopathic indifference to the human cost of their actions."
He suggests Liberman's fluctuating support has been "timed to cause
embarrassment to the Democratic
leadership. [...] one can hardly be all that surprised that he's making
problems
for the Obama administration's #1 domestic priority. After all,
Lieberman took the view that John McCain would be the better President."

Debate Stacked Against Reform Washington Monthly's Steve Benen explains how Lieberman exploits the weakness. "It's the leverage trump-card dynamic that's been apparent
throughout the debate -- the left doesn't want reform to fail; the
right doesn't care," he writes. "For the left, failure is not an option, because the human,
political, economic, and fiscal consequences are too severe. For the
right, failure is entirely acceptable, if not preferable. Both sides
know what the other side is thinking.
The result is less of a negotiation and more of a hostage standoff,
with Joe Lieberman playing the role of the proverbial gunman who isn't
bluffing."

He Wants Attention Foreign Policy's Marc Lynch scoffs, "Joe Lieberman
firmly holding the line in his principled demands that everybody pay
attention to Joe Lieberman. Not exactly a surprise."